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• Successful preparation of Fe 3 O 4 /PbZr 0.2 Ti 0.8 O 3 /Zn 0.95 Co 0.05 O multiferroic heterostructure. • Magnetic and resistive states of heterostructure are synchronously regulated by polarization bias at room temperature. • Significant enhancement of room-temperature magnetoelectric coupling effect is achieved in multiferroic heterostructure. • Fe 3 O 4 /PbZr 0.2 Ti 0.8 O 3 /Zn 0.95 Co 0.05 O multiferroic heterostructure presents four distinct magnetoresistances. A novel multiferroic heterostructure composed of Fe 3 O 4 /PbZr 0.2 Ti 0.8 O 3 (PZT)/Zn 0.95 Co 0.05 O(ZCO) is prepared on the Pt(1 1 1)-Ti-SiO 2 -Si substrate in this work to achieve the synchronous electric regulation on magnetic and resistive states at room temperature. When the polarization direction of the PZT layer is reversed with the write voltage, the depletion or accumulation of oxygen vacancies is formed at the PZT/ZCO interface, exhibiting the resistance switching between high and low resistive states with a ratio up to 1.19 × 104. Meanwhile, based on the interfacial charge effect and bound magnetopolaron (BMP) theory, magnetic modulation with a magnetoelectric (ME) coupling coefficient up to 133.2 Oe/V is realized at room temperature. More interestingly, by measuring the magnetoresistance, four distinct resistance states are displayed in this multiferroic structure with the ferroelectric reversal. Our results show that the multiferroic system containing both ferromagnetic and diluted magnetic semiconductor can simultaneously realize magnetoelectric coupling and resistance switching at room temperature. The magnetic signal can also be converted into an electrical signal based on the magnetoresistance effect. [ABSTRACT FROM AUTHOR]

• Magnetic properties of a Fe-Si-B amorphous alloy with stress gradient were studied. • Magnetic anisotropy and coercivity evolve separately. • Compressive stress hinders the reversible magnetization vector rotation. • Coercivity is irrelevant to the coherent stress. The magnetic properties and domain structure of a Fe 78 Si 9 B 13 amorphous alloy with a stress gradient from upper to the lower surface were investigated. We found that the magnetic properties of the samples vary significantly upon stress variation. Specifically, the magnetic anisotropy increases linearly with the maximum stress, whereas the coercivity, although higher than the one without stress, remains reasonably small. The phase contrast in magnetic force microscopy image and the fingerprint-like domains in magneto-optical Kerr microscopy images for ribbon surface with compressive stress demonstrate the presence of perpendicular anisotropy due to the magneto-elastic coupling. As a result, the compressive stress hinders the reversible magnetization vector rotation and makes the magnetization hard to be saturated. However, the stress causes no irreversible effects, neither on the domain wall movement nor on the magnetization rotation. Thus it is irrelevant to the coercivity. These results are different from the situation of the inhomogeneously distributed quenched-in stress enlarging the coercivity in Fe-based amorphous alloys. [ABSTRACT FROM AUTHOR]